Tangent equation of point P (4, - 2) on circle X & sup2; + Y & sup2; - 2x + 4y-4 = 0

Tangent equation of point P (4, - 2) on circle X & sup2; + Y & sup2; - 2x + 4y-4 = 0

The standard equation of a circle is (x-1) ^ 2 + (y + 2) ^ 2 = 9. The point P (4, - 2) is just a point on the circle. When you draw a graph, you can easily see that the tangent is x = 4